<?php

class LtDb
{
    public $configHandle;

    public $group;
    public $node;
    protected $dbh;

    public function __construct()
    {
        if (!$this->configHandle instanceof LtConfig) {
            if (class_exists("LtObjectUtil", false)) {
                $this->configHandle = LtObjectUtil::singleton("LtConfig");
            } else {
                $this->configHandle = new LtConfig;
            }
        }
    }

    public function init()
    {
        $this->dbh = new LtDbHandle;
        $this->dbh->configHandle = $this->configHandle;
        $this->dbh->group = $this->getGroup();
        $this->dbh->node = $this->getNode();
        $this->dbh->init();
    }

    public function getDbHandle()
    {
        return $this->dbh;
    }

    public function getTDG($tableName)
    {
        $tg = new LtDbTableDataGateway;
        $tg->configHandle = $this->configHandle;
        $tg->tableName = $tableName;
        $tg->createdColumn = 'created';
        $tg->modifiedColumn = 'modified';
        $tg->dbh = $this->dbh;
        return $tg;
    }

    public function getSqlMapClient()
    {
        $smc = new LtDbSqlMapClient;
        $smc->configHandle = $this->configHandle;
        $smc->dbh = $this->dbh;
        return $smc;
    }

    public function changeNode($node)
    {
        $this->node = $node;
        $this->dbh->node = $node;
    }

    protected function getGroup()
    {
        if ($this->group) {
            return $this->group;
        }
        $servers = $this->configHandle->get("db.servers");
        if (1 == count($servers)) {
            return key($servers);
        }
        return false;
    }

    protected function getNode()
    {
        if ($this->node) {
            return $this->node;
        }
        $servers = $this->configHandle->get("db.servers");
        if (1 == count($servers[$this->getGroup()])) {
            return key($servers[$this->getGroup()]);
        }
        return false;
    }
}